Agricultural combine are used to harvest grain (e.g., wheat, corn, barley, etc.) from plants growing upon an agricultural field. Combines combine the harvesting operations of reaping, gathering, threshing, and winnowing, or cleaning, which, in earlier years, were separately performed; hence, the name "combine".
A combine typically includes a frame, a main body supported thereby, and ground support devices such as wheels and/or crawler treads to support the frame upon the surface of a field. A combine may be an implement towed and steered by a vehicle such as a tractor and having internal crop processing devices powered by a power takeoff (PTO) shaft associated with the tractor, or it may itself be a vehicle powered by an on-board engine, or other prime mover, wherein at least some of the ground support devices are controllably steerable to guide the combine over the field.
In either event, combines generally include a reaping portion (i.e., a header) attached to the front thereof for cutting, snapping or otherwise severing the crop plant stalk near the soil surface and gathering the cut plants or crop material for additional processing operations. The header is generally relatively wide such that a plurality of rows of crop may be harvested simultaneously, and typically is configured to transversely convey the crop materials toward the transverse center of the combine. A feed conveyor or feeder receives the crop material from the header and conveys the material rearwardly into a chamber inside the main body for additional processing.
The chamber includes a threshing portion or thresher which receives crop material from the feeder at an inlet end and removes kernels of grain from the received material to separate the grain from non-grain materials (i.e., "trash") such as stalks, straw, husks, cobs, etc. The thresher includes a generally cylindrical rotating member, or rotor, rotating within a generally cylindrical static casing, or rotor cage.
A combine is generally configured with a thresher with a rotor axis of rotation either horizontally and transversely disposed (i.e., a "conventional" thresher) or horizontally and longitudinally disposed (i.e., an "axial flow" thresher). Axial flow threshers have a forwardly disposed inlet end and a rearwardly disposed outlet end, with the outlet end generally being disposed slightly higher than the inlet end. Examples of combines having axial flow threshers are models within the 2300 Series of Axial-Flow.TM. combines produced by Case Corporation of WI, the assignee of the present application. The present invention is equally applicable, however, to combines which are configured with either conventional or axial flow threshers.
The rotor has a ribbed outer surface and a fixed radius, while the rotor cage has a vaned inner surface. At least some of the rotor cage's vanes are spirally configured such that rotation of the rotor within the rotor cage transports the crop materials rearwardly as well as circumferentially. The rotor cage has a significantly larger inside diameter than the rotor's outside diameter, so that a large rotor cage gap exists between the rotor's outer surface and the rotor cage's inner surface. A lower portion of this rotor cage gap contains an arcuate and perforated device known as a "concave", spaced apart from the rotor by a concave gap smaller than the rotor cage gap. The concave gap may be adjusted by changing the radius of the concave for differing crops, crop moisture levels, and other varying conditions. The perforated concave has a plurality of apertures of a size slightly larger than that of a kernel of the grain being harvested so that kernels freed from the trash may fall by gravity out of the thresher into a collecting grain pan beneath the concave. Most of the threshing action occurs within the concave gap. The concave includes a plurality of concave sections, and may also include at least one additional rearwardly disposed perforated member or "grate". Collectively, the assemblage of individual concave sections and, if present, grate sections, is referred to as a concave.
While dust and small bits of trash fall through the apertures into the grain pan with the grain, most of the trash is too large to fall through the apertures and thus continues being transported rearwardly through the thresher to exit via an open outlet end of the thresher. The trash is expelled from the rear of the combine by air flow from a cleaning air fan, which may be assisted by a rotating open impeller, or beater, to fall on the field surface. Incompletely threshed material, or tailings, too heavy to be blown out, fall into a chaffer sieve for deposit into a tailings pan for conveyance by a tailings conveyor to the inlet end of the thresher for re-threshing.
A conveyor, typically including at least one grain augur, runs through the grain pan and transports the grain rearwardly to a grain cleaning portion of the combine, where dust and small bits of trash entrained therewith are removed by the combined actions of at least one horizontally disposed vibrating or oscillating screen, or sieve, and air flow through and over the sieve provided by the cleaning air fan. To provide efficient operation with various types of grain and operating conditions, sieve opening sizes and cleaning air flow rates are independently adjustable, the latter by adjustment of fan speed and/or fan outlet restriction; e.g., an outlet damper.
Trash particles removed from the grain are carried out the combine by the air stream from the cleaning air fan for deposit upon the field, while the relatively heavy grain kernels fall through the sieve into a horizontally disposed cleaned grain pan. A conveyor, typically a cleaned grain augur, runs transversely through the cleaned grain pan to transport the cleaned grain to another conveyor, typically a generally vertically disposed elevator, which lifts the cleaned grain into a storage bin or grain tank which may be periodically emptied into a large truck or transfer vehicle placed alongside the combine through a horizontally disposed unloading augur.
If it is desired to use a combine configured to harvest one type of grain (e.g., wheat) to harvest another type of grain (e.g., corn), the combine must generally be reconfigured for the new crop (which may have a different structure, row spacing, and grain kernel size and mass) by substituting a different header and, in some cases, different concaves, rotor and sieves. It is then necessary to estimate the average crop yield per acre and moisture level in order to select preliminary settings for combine ground speed, header speed, feeder speed, rotor speed, concave gap, sieve oscillation frequency and amplitude, and cleaning air fan speed or outlet restriction.
To efficiently harvest the new crop, the operator closely monitors many operational parameters of the combine and makes corresponding adjustments to various settings of the combine. The adjustable settings of the combine typically include the engine speed, ground speed, header reel speed, feeder speed, rotor speed, sieve speed, cleaning air fan speed, concave gap, sieve opening size, header height, header attitude, etc. The adjustments may be made in response to the operator's own observations of crop material level within the header, load at various points of the power transmission, crop yield rates, grain loss at the rotor or sieves; flow rates of clean grain, tailings, cleaning air, and engine fuel; grain bulk quality in terms of trash and fine fracture particles in the cleaned grain; and grain kernel individual quality in terms of the extent to which grain kernels are fractured during the threshing process.
Many adjustments are interactive to varying degrees depending in part on a particular harvest's grain type, plant height, health, uniformity, moisture level, etc., and desired harvesting efficiency in terms of acceptable level of grain loss versus yield rate, engine fuel consumption rate, and the time available for harvesting a field before the combine and attendant transfer vehicles are needed at another field. Since crop characteristics vary throughout a field (e.g., due, to variation in application rates of seed, fertilizers, pesticides, herbicides, and due to soil types, nutritional levels, drainage, pitch, storm damage, etc.), the operator must continuously monitor the operational conditions of the harvest and must correspondingly adjust settings of the combine to maximize crop yield while containing the costs associated with harvesting.
Thus, it is apparent that operation of a combine requires a considerable amount of skill, close attention and diligence for long periods of time. Locating the operator's station in a sealed cab supplied with filtered and conditioned air increases operator comfort and aids the operator in concentrating on the harvesting, but also reduces the noise level within the cab which, while beneficial for the same reason, reduces the operator's ability to hear changes in the sounds of the various parts of the combine's apparatus which may otherwise alert him to changes in harvest conditions.
Recent developments have alleviated some demands placed on the combine operator while improving harvesting efficiency. Some of the developments include Global Positioning System (GPS) equipment placed on board the combine which, when combined with a suitable harvest and combine data acquisition system, reduces the need for the operator to manually record data; systems for monitoring, displaying, and recording in real time parameters such as feed rate, yield rate, grain loss rates, moisture level, grain level within the grain tank, various loads and speeds; and control systems for controlling such parameters. Such systems typically use potentiometric, capacitative, piezoelectric, variable reluctance, photoelectric and strain gage sensors. Despite advances made in throughput, efficiency, and ease of operation, however, there remains significant room for improvement.
It would be advantageous to provide an instrument and control system for a combine having machine vision apparatus and a data processing unit ("DPU"), the machine vision apparatus disposed to view crop materials being processed by the combine, generate a spectral color signal representing hue of the crop materials, and transmit the spectral color signal to the DPU, the DPU being used to chromatically analyze the image represented by the spectral color signal. It would be advantageous to place such machine vision apparatus at any of several locations on the combine to visually sense the crop materials being processed from any of the locations. It would also be advantageous to use the crop image signal produced by such machine vision apparatus as an input used for controlling settings of various crop processing systems.